以节能为目标的小基站周期性开启研究

Research on periodical opening of small base-stations for energy conservation

当前,无线通信业务朝着高数据率、高动态性方向发展,给传统蜂窝网络带来了极大的挑战。对此,引入小基站(例如:微基站、皮基站)关断机制的异构蜂窝网络是一种有效的解决方案,可以兼顾服务质量和网络能耗。系统进行小基站开关调度须基于小基站与用户通信的信道状态信息,然而,由于关断的小基站处于静默状态,系统无法通过信道估计获得上述信息。为了解决这一问题,该文提出了小基站周期性开启方案。在该方案中,系统周期性地开启小基站,获得用户与小基站通信的信道信息;用户通过宏基站发起接入请求时,系统利用最近一次小基站开启时获得的信道信息进行网络调度决策。周期的设计是影响该方案实施效果的关键性因素,一方面决定了小基站周期性开启需要付出的能量消耗代价,另一方面又决定了信道信息的实时性,从而影响网络调度的效果。该文关注网络的总能耗,将其分为小基站周期性开启消耗的能量和用户服务消耗的能量,并得到了能够实现网络总能耗最小化的周期设计方案。

The development of wireless traffic toward high data rates and high dynamism has brought great challenges to traditional cellular networks. Heterogeneous networks with small base station sleeping are an effective solution to this problem, which balances service quality and network energy consumption. The scheduling of small base-stations should be based on the status information about the channel between users and small base-stations. However, once the small base-stations are turned off, they switch to the sleeping mode, thus the system is unable to obtain the aforementioned information. To solve this problem, this paper presents a periodical opening mechanism for small base-stations： the system periodically opens the small base-stations to obtain channel information between the users and the small base-stations; once the users send an access request via the macro base-stations, the system makes the correspondent decision on the basis of the channel information obtained when the small base-stations were open at the last time. The design of the opening cycle is a key factor influencing the effect of this mechanism. This paper divides the total energy consumption of the network into two parts, the energy consumption for periodical opening of small base-stations and the energy consumption for user service, and works out an optimal cycle design solution balancing the two parts and minimizing the total energy consumption.